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Pinus yunnanensis is an important component of China's economic development and forest ecosystems. The growth of P. yunnanensis seedlings experienced a slow growth phase, which led to a long seedling cultivation period. However, asexual reproduction can ensure the stable inheritance of the superior traits of the mother tree and also shorten the breeding cycle. The quantity and quality of branching significantly impact the cutting reproduction of P. yunnanensis, and a shaded environment affects lateral branching growth, development, and photosynthesis. Nonetheless, the physiological characteristics and the level of the transcriptome that underlie the growth of lateral branches of P. yunnanensis under shade conditions are still unclear. In our experiment, we subjected annual P. yunnanensis seedlings to varying shade intensities (0%, 25%, 50%, 75%) and studied the effects of shading on growth, physiological and biochemical changes, and gene expression in branching. Results from this study show that shading reduces biomass production by inhibiting the branching ability of P. yunnanensis seedlings. Due to the regulatory and protective roles of osmotically active substances against environmental stress, the contents of soluble sugars, soluble proteins, photosynthetic pigments, and enzyme activities exhibit varying responses to different shading treatments. Under shading treatment, the contents of phytohormones were altered. Additionally, genes associated with phytohormone signaling and photosynthetic pathways exhibited differential expression. This study established a theoretical foundation for shading regulation of P. yunnanensis lateral branch growth and provides scientific evidence for the management of cutting orchards. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive examination of Pinus kesiya var. langbianensis (Pinus kesiya var. langbianensis), the primary resin-extraction tree species in Yunnan Province, China. In this study, we formulated different concentration gradients of 0.25%, 0.5%, 1%, and 2% of diquat solution as tapping stimulant to test the effect of different concentrations on the resin gain rate of Pinus kesiya, and analyzed the relationship between anatomical structure, major chemical composition of turpentine and resin yield by methods such as wood anatomy and chemical composition analysis of turpentine. The primary focus of the investigation was on exploring the interrelationships among resin-tapping stimulants, anatomical structures, turpentine components, and resin yield. Research findings demonstrate a significant enhancement in resin production due to the application of stimulants, with the highest increase rate reaching 55% in a specific group, while others achieved approximately 30% increments. Moreover, measurement data about resin duct dimensions indicate a noteworthy increase in resin duct area for the stimulant-treated group compared to the control group. However, it should be noted that the impact on resin duct area by varying stimulant concentrations was relatively minor. Furthermore, continuous observation of resin extraction from different resin-yield classes of P. kesiya revealed insignificant variation in resin yield over time for the low and moderate resin-yield groups. In contrast, the high resin-yield group exhibited a gradual increase in resin production. Interestingly, the high resin-yield group exhibited the smallest resin duct area, but the highest resin duct density, indicating an interconnectedness of resin duct-related data that influences resin yield. Additionally, correlative investigations between anatomical structures and resin yield demonstrate a positive correlation between resin duct area and resin yield, total resin production, and average resin yield. This underscores the importance of resin duct area as a significant factor in resin production. On the other hand, the influence of stimulant concentrations on the turpentine components was found to be negligible. Overall, the correlation results suggest that turpentine components cannot reliably predict or differentiate between high and low resin-yield trees. This study provides a comprehensive analysis of the interrelationships among stimulants, anatomical structures, and turpentine components, offering a theoretical foundation for the resin extraction and resin processing industries in Yunnan Province. [ABSTRACT FROM AUTHOR]

Previously, only three species of the genus Neurigona Rondani of the subfamily Neurigoninae were known from Yunnan Province. Here, we reviewed the species of Neurigona from Yunnan and added the following seven new species: N. apicilata sp. nov., N. basicurva sp. nov., N. brevidigitata sp. nov., N. convexa sp. nov., N. huanglianshana sp. nov., N. quadrimaculata sp. nov., and N. ventriprocessa sp. nov. All seven new species are sympatric and were collected from below a reservoir in the Huanglianshan Nature Reserve in Yunnan using three Malaise traps in 2019. This suggests a very high species richness in the Yunnan fauna. A key to the species of Neurigona from Chinese mainland is provided. [ABSTRACT FROM AUTHOR]

Background: School bullying victimization is associated with increased risk of anxiety in children and adolescents. However, little is known about the role of resilience in this association. The purpose of this study was to investigate the possible mediation by resilience in this association in a large group of Chinese children and adolescents. Methods: A population-based cross-sectional study adopting two-stage simple random cluster sampling was implemented in Yunnan province, southwestern China. A comprehensive questionnaire was used to collect information from the participants. Among all the participants, 4624 were included in the final analysis. Descriptive statistics were used to present general characteristics of the study participants. Univariate and multivariate logistic regression models were adopted to estimate crude and adjusted associations among bullying victimization, anxiety, and resilience. A path model was used to analyze the hypothesized mediation by resilience in the association between bullying victimization and anxiety. Results: Analytical results of multivariate logistic regression models suggested that bullying victimization was significantly associated with anxiety in Chinese children and adolescents; compared with individuals who had not been bullied, victims of bullying were more likely to experience anxiety symptoms, with an adjusted odds ratio (OR) of 3.02 (95% CI 2.46–3.71). Path analysis revealed a prominent mediating effect of resilience in the association between bullying victimization and anxiety, accounting for 31.89% of the total association. Further analysis indicated that, among the five dimensions of resilience, emotional regulation, interpersonal assistance, and family support were significant mediators, accounting for 30.34%, 10.79%, and 8.35% of the total association. Conclusions: Our major findings highlighted the promising role of resilience-based intervention measures in reducing the risk of anxiety associated with school bullying victimization in Chinese children and adolescents. [ABSTRACT FROM AUTHOR]

Although evidence in supporting the associations between childhood maltreatment (CM), parenting style and anxiety in children and adolescents exists, few high-quality analytical epidemiological studies which focusing on clinically diagnosed anxiety disorders (AD) had been published. The aim of this study was to further corroborate the associations between CM, parenting style, and AD in a large representative sample of Chinese children and adolescents. Study subjects were derived from the Mental Health Survey for Children and Adolescents in Yunnan (MHSCAY), a population-based cross-sectional program. Individually matched case-control study design was adopted. Univariate and multivariate conditional binary logistic regression models were used to estimate the associations between CM, parenting style and AD. Dose-response trends were estimated using the Cochran-Armitage Chi-square test. A series of stratified analyses were conducted to explore effect modification on exposure-outcome association by some important features. Totally we screened out 202 cases and 404 matched controls, with an age mean of 14.43 years. Conditional logistic regression models revealed that EA and a higher level of parental over-protection were significantly associated with increased risk of AD, with adjusted ORs of 3.39 (95 % CI: 2.07–5.56) and 1.93 (95 % CI: 1.28–2.90). Stratified analysis identified noticeable effect modification by sex, age, and whether the only child in the family. Major findings of this study suggested that children and adolescents who had experienced EA or raised up by over-protective parents are at increased risk of AD. Targeted intervention measures should be developed and implemented for these high-risk youths. [ABSTRACT FROM AUTHOR]

Background: After the scale-up of antiretroviral therapy (ART) for HIV infected people, increasing numbers of patients have pretreatment drug resistance (PDR). In this study, the prevalence of PDR was evaluated in adults initiating antiretroviral therapy in China. Methods: Blood samples were obtained from 1943 patients who initiated antiretroviral therapy (ART) in 2017 from 13 provinces or cities in China. Pol sequences were used to analyze drug resistance and construct transmission networks. Logistic regression model was used to estimate the potential factors associated with PDR. Results: In total, 1711 eligible patients (76.0% male; 87.8% aged ≥ 25 years) were included, of which 117 (6.8%) had PDR. The highest rates of PDR were 12.2% in Liangshan Prefecture of Sichuan and 9.3 and 8.9% in Dehong and Lincang Prefecture of Yunnan. A multivariate logistic regression analysis revealed that PDR was significantly higher among intravenous drug users (adjusted Odds Ratio (aOR) = 2.64, 95% CI: 1.57–4.44) and individuals from Liangshan, Dehong, and Lincang (aOR = 2.04, 95% CI: 1.26–3.30). In total, 754 sequences were used to generate 164 transmission networks. Five transmission networks had two or three sequences containing the same mutations, two networks contained subjects from Liangshan, and one network contained subjects from Dehong. Conclusions: Overall, the PDR prevalence was moderate, with a particularly high prevalence in areas with severe HIV epidemics. These results indicate the importance of continuous PDR monitoring in patients initiating antiretroviral therapy. [ABSTRACT FROM AUTHOR]

To understand the distribution of the cultivable fungal community in plant tissues and the associations of these fungi with their surrounding environments during the geographical expansion of an invasive plant, Ageratina adenophora , we isolated the cultivable fungi from 72 plant tissues, 12 soils, and 12 air samples collected from six areas in Yunnan Province, China. A total of 4066 isolates were investigated, including 1641 endophytic fungi, 233 withered leaf fungi, 1255 fungi from air, and 937 fungi from soil. These fungi were divided into 458 and 201 operational taxonomic units (OTUs) with unique and 97% ITS gene sequence identity, respectively. Phylogenetic analysis showed that the fungi belonged to four phyla, including Ascomycota (94.20%), Basidiomycota (2.71%), Mortierellomycota (3.03%), and Mucoromycota (0.07%). The dominant genera of cultivable endophytic fungi were Colletotrichum (34.61%), Diaporthe (17.24%), Allophoma (8.03%), and Fusarium (4.44%). Colletotrichum and Diaporthe were primarily isolated from mature leaves, Allophoma from stems, and Fusarium from roots, indicating that the enrichment of endophytic fungi is tissue-specific and fungi rarely grew systemically within A. adenophora. In the surrounding environment, Alternaria (21.46%), Allophoma (19.31%), Xylaria (18.45%), and Didymella (18.03%) were dominant in the withered leaves, Cladosporium (22.86%), Trichoderma (14.27%), and Epicoccum (9.83%) were dominant in the canopy air, and Trichoderma (27.27%) and Mortierella (20.46%) were dominant in the rhizosphere soils. Further analysis revealed that the cultivable endophytic fungi changed across geographic areas and showed a certain degree of variation in different tissues of A. adenophora. The cultivable fungi in mature and withered leaves fluctuated more than those in roots and stems. We also found that some cultivable endophytic fungi might undergo tissue-to-tissue migration and that the stem could be a transport tissue by which airborne fungi infect roots. Finally, we provided evidence that the fungal community within A. adenophora was partially shared with the contiguous environment. The data suggested a frequent interaction between fungi associated with A. adenophora and those in surrounding environments, reflecting a compromise driven by both functional requirements for plant growth and local environmental conditions. [ABSTRACT FROM AUTHOR]

The independent associations among childhood maltreatment (CM), parenting style, and school bullying in children and adolescents have not been adequately discussed. Epidemiological evidence of higher quality is still scarce. We intend to investigate this topic by using a case–control study design in a large sample of Chinese children and adolescents. Study participants were chosen from the Mental Health Survey for Children and Adolescents in Yunnan (MHSCAY), a mega ongoing cross-sectional study. The combined database from four study sites was used. The population-based case–control study was individually matched by study site, age, sex, race, left-behind status, whether a single child, and whether a boarding student. Cases were observed to have a significantly higher prevalence of CM, higher scores for parental rejection and over-protection, and lower scores for parental emotional warmth. Multiple conditional logistic regression revealed that CM, especially emotional abuse (EA) and sexual abuse (SA), were associated with a prominently increased risk of school bullying involvement, with adjusted odds ratio (OR) of 2.28 (95 % CI: 2.03, 2.57) and 1.90 (95 % CI: 1.67, 2.17). Subsequent analysis further corroborated the robustness of EA–bullying and SA–bullying associations. Although parenting style generally showed a weaker association with school bullying, a higher level of parental rejection was related to an increased risk of bullying victimization. Chinese children and adolescents who are victims of EA or SA, or experienced a higher level of parental rejection, are more vulnerable to school bullying. Targeted interventions should be designed and implemented. • CM, especially EA and SA, were associated with increased risk of school bullying involvement. • Parental rejection was related to school bullying victimization. • Victims of EA and SA, and adolescents reported higher level of parental rejection should be targeted for intervention. [ABSTRACT FROM AUTHOR]

Objective: We aimed to investigate the mediation of social support in the association between school bullying and suicidal risk among a large group of Chinese children and adolescents.Method: In this two-wave cross-sectional study, we analyzed 6,063 children and adolescents from southwest China. A two-stage simple random clustering sampling method with probability proportionate to sample size design had been used to select study subjects. Univariate and multivariate Logistic regression models were adopted to determine the inter-associations between school bullying, suicidal risk indicators, and social support. Path models were further fitted to estimate the mediation of social support.Results: Compared with students who were not involved in school bullying, only victimization was associated with increased suicidal risk, the adjusted ORs for suicidal ideation, suicidal plan, and suicidal attempt were 2.06 (95% CI: 1.61-2.65), 2.07 (95% CI: 1.62-2.64), and 2.41 (95% CI: 1.90-3.05), respectively. Path model indicated that parental social support significantly mediated the association between bullying victimization and suicidal risk. For different types of victimization, only relational bullying victimization was associated with increased suicidal risk, social support from classmates and close friends presented as significant mediators.Limitations: Causal inference cannot be made because of cross-sectional study design. Information was collected by using self-reporting method, the possibility of information bias exists. Generalization of study results could be limited.Conclusions: Intervention measures on improving parental and peer social support may be effective in reducing school bullying victimization associated suicidal risk for Chinese children and adolescents. [ABSTRACT FROM AUTHOR]